John kobe



@stent @time JOHN ROBB, 0F NEW YORK, N. Y.

Letters Patent No. 99,595, dated February 8, 1870.

IMPROVED MODE OF SPLITTING' ROCK.

The Schedule referred to in these Letters Patent:- and making part ofthe same.

To all whom it may concern:

Be it known that I, JOHN ROBE, of New York city, in the county of NewYork, and State of New York, have invented a new and useful Improvementin Splitting-1{ock; and I do hereby'declare that the following isl afnll, clear, and exact description thereof', which will enable othersskilled in the art to make and use 'the same, reference being had to theaccompanying The invention consists in filling or nearly filling theholes, drilledin the same way as for blasting, with water or otherliquids, and then inserting plungers fitted to work as tightly aspossible above the water, and subjectin g the said plungel's to theaction of great weights, halrnners, or other devices, let fall uponthem, or otherwise imparting great concussive force, which is, throughthe medium ofthe water, expended upon the side walls ofthe holes, in thedirection best calculated for separating the rocks.

. The drawing represents a section through a rock, drilled and preparedwith water, and a plunger for operation, according t-o my improvement.

and D, the plunger or pistou.

The hole B is nearly filled with water, asV designatedv by letter C.

These pistons may be operated singly or collectively in rows, aspreferred or required in the nature of` the work in hand, the hammersbeing arranged to strike simultaneously, when used collectively.

This mode is preferable to blasting, not only because it is lessdangerous, but also because all the force is expended in the requireddirection, whereas in blasting, a large measure is lost bythe givingaway of the packing as soon as it is freed bythe starting of the rock.

' Having thus described my invention,

I claim as new, and desire to secure by Letters Patent-Thehereimdescribed improved mode of' splitting or separating rocks, bymeans of' concussive force imparted to water or other liquids placed inthe holes made in the rock, through the medium of plunger D, above thewater, fitting the holes, and arranged to receive the said force from ahammer, drop, or other device, all substantially as specified.

' 'Ihe above specification of' my invention, signed by me, this 29th dayof July, 1869. y

' JOHN ROBB.

Witnesses:

GEO. W. MABEE, ALFRED LURGOTT.,

